factor-lang

I'm not seeing any output from my Hello World program. $ cat hello.factor USE: io IN: hello : hello ( -- ) "Hello World!" print ; MAIN: hello $ factor hello.factor $ (No output) $ factor -run=hello Vocabulary does not exist name "hello" $ factor -run=hello hello.factor $ (No output) MAIN: defines an entry point for a vocabulary when the vocabulary is passed to run , not necessarily when it is "loaded" from the command line, as you're doing above. The easiest way to make this work is to simply issue "hello" run from the UI listener. To actually call the hello word as a script, simply place a

Cleave is a really useful combinator for minimising code duplication. Suppose I want to classify Abundant, Perfect, Deficient numbers : USING: arrays assocs combinators formatting io kernel math math.order math.primes.factors math.ranges sequences ; IN: adp CONSTANT: ADP { "deficient" "perfect" "abundant" } : proper-divisors ( n -- seq ) dup zero? [ drop { } ] [ divisors dup length 1 - head ] if ; : adp-classify ( n -- a/d/p ) dup proper-divisors sum <=> { +lt+ +eq+ +gt+ } ADP zip H{ } assoc-clone-like at ; : range>adp-classes ( n -- seq ) 1 swap 1 <range> [ adp-classify ] map ADP dup [ [ [ =

I recently took a look at Factor , and the idea of having a language based around the concept of a stack is very interesting. (This was my first encounter with a stack-oriented language.) However, I don't see any practical advantages of such a paradigm. To me, it just seems like more trouble than it's worth. Why would I use a stack-oriented language such as Factor or Forth? I'm ignoring factors (excuse the pun) such as the availability of tools and libraries. I'm asking only about the language paradigm itself. Stack orientation is an implementation detail. For example, Joy can be implemented